(Not Applicable)
(Not Applicable)
The present invention relates generally to coffee bean roasters, and more particularly to a coffee bean roaster with recirculated, filtered exhaust airflow.
It has long been recognized that the most aromatic and tasteful coffee beverages result from green coffee beans which are freshly roasted, ground and brewed. The flavor of coffee is developed by roasting which results in a pyrolysis process of oils in the coffee beans. Green unroasted coffee beans have a film-like covering which effectively excludes air and moisture thereby protecting the coffee beans. This protective covering on the coffee beans is removed during the roasting process as chaff. Removal of this protective covering leaves roasted coffee beans exposed which results in oxidation of the oils in the coffee beans.
Coffee beans begin losing their flavor and aroma once they are roasted because of such oxidation of the oils. Roasted coffee beans will maintain its flavor reasonably well for approximately one week if sealed in an air tight container to minimize oxidation of the oils. Ground roasted coffee loses a significant amount of flavor after being ground, and will maintain its flavor reasonably well for only a few days. In contrast, green coffee beans may be kept for years with minimal effects upon their flavor characteristics, other than a mellowing as with aging of a fine wine.
Traditionally, retail outlets for roasted coffee beans, ground coffee and coffee beverages purchase roasted coffee beans from distributors. In order to raise the level of coffee freshness, however, some retail outlets have begun to roast green coffee beans on-site in coffee bean roasters.
The typical roasting process results in smoke and various gases evolved from the coffee beans. Such smoke and fumes need to be exhausted from the coffee bean roaster in order to prevent the flavor characteristics of the roasted coffee beans being affected. In the retail settings, direct ventilation piping from the coffee bean roaster to outside of the establishment is typically required. Such ventilation piping may require modifying the premises for costly, inconvenient installation of such piping through a wall or ceiling. Such installation may be considered aesthetically unpleasing. Moreover, such installation may undesirably subject the establishment to any variety of health and safety regulations. Further, direct venting of the resulting smoke and fumes is not considered environmentally sensitive.
It is therefore evident that there exists a need in the art for a more efficient apparatus and method of handling the exhaust smoke and fumes from coffee bean roasters in comparison to the prior art.
In accordance with an embodiment of the present invention, there is provided a coffee bean roaster with recirculated, filtered exhaust airflow. The coffee bean roaster includes a roasting drum sized and configured to receive coffee beans for roasting therein. The roasting drum has a drum airflow inlet and a drum airflow outlet for exhausting airflow from the roasting drum. The coffee bean roaster further includes a blower configured to blow airflow through the drum airflow inlet for venting the roasting drum. The coffee bean roaster further includes a fluid filter having a filter airflow inlet and a filter airflow outlet. The filter airflow inlet is in fluid communication with the drum airflow outlet. The fluid filter is configured to filter airflow from the roasting drum. The filter airflow outlet is in fluid communication with the blower for recirculating airflow into the roasting drum.
As such, during and after the roasting process, airflow containing smoke and fumes evolved from the coffee beans may be vented from the roasting drum to the fluid filter. The fluid filter effectively scrubs the airflow of particulates and gases associated with smoke and fumes. The cleansed airflow is then recirculated to the blower and the roasting drum. Advantageously, such recirculation avoids usage of ventilation piping from the roasting drum to outside of the establishment as in prior art coffee bean roasters. In this regard, the present invention is contemplated to provide a coffee bean roaster which is cost effective, aesthetically pleasing and environmentally sensitive in comparison to prior art devices. Moreover, because of the closed, self contained nature of the present invention, a proprietor of an establishment utilizing a coffee bean roaster of the present invention may display the same for customers to readily observe. In this regard, customers can see for themselves the freshness of roasted coffee beans and ground coffee beans and beverages obtained therefrom.
In an embodiment of the present invention, the fluid filter is a water-based filter. Further, the coffee bean roaster includes a fluid source sized and configured to provide fluid to the fluid filter. The fluid filter has at least one screen, which may comprise multiple screens. The fluid source is sized and configured to distribute fluid across the screen. The screen is positioned between the filter airflow inlet and the filter airflow outlet for passage of airflow through the screen from the filter airflow inlet to the filter airflow outlet. The screen has an upper end and a lower end, and the fluid source is sized and configured to dispense fluid adjacent the upper end for distributing fluid across the screen towards the lower end. The coffee bean roaster further includes a fluid reservoir sized and configured to receive fluid from the screen. The fluid reservoir is disposed in fluid communication with the fluid source for recirculating fluid to the fluid filter.
The coffee bean roaster may further include a secondary filter sized and configured to remove fluid vapor from the airflow. The secondary filter is disposed in fluid communication with the filter airflow outlet of the fluid filter and the blower. A fluid source sized and configured may be provided to provide fluid to the fluid filter. The fluid source may be sized and configured to receive condensed fluid vapor removed from the airflow by the secondary filter for recirculation to the fluid filter. The coffee bean roaster may further include a chaff collector sized and configured to remove chaff from the airflow. The chaff collector may be disposed in fluid communication with the roasting drum and the filter airflow inlet of the fluid filter. The coffee bean roaster may further include a drum housing. The roasting drum and the blower are disposed within the drum housing. The fluid filter may further include a filter housing. The filter housing may be integrated with the drum housing. Alternatively, the filter housing may be detachable from the drum housing.
In accordance with another embodiment of the present invention, there is provided an exhaust filter system for use with a coffee bean roaster. The coffee bean roaster has a roasting drum sized and configured to receive coffee beans for roasting therein. The roasting drum has a drum airflow inlet and a drum airflow outlet for exhausting airflow from the roasting drum. The coffee bean roaster further has a blower configured to blow airflow through the drum airflow inlet for venting the roasting drum. The exhaust filter system includes a fluid filter having a filter airflow inlet and a filter airflow outlet. The filter airflow inlet is disposable in fluid communication with the drum airflow outlet. The fluid filter is configured to filter airflow from the roasting drum. The filter airflow outlet is disposable in fluid communication with the blower for recirculating airflow into the roasting drum.
In an embodiment of the present invention, the fluid filter is a water-based filter. Further, the exhaust filter system includes a fluid source sized and configured to provide fluid to the fluid filter. The fluid filter has at least one screen, which may comprise multiple screens. The fluid source is sized and configured to distribute fluid across the screen. The screen is positioned between the filter airflow inlet and the filter airflow outlet for passage of airflow through the screen from the filter airflow inlet to the filter airflow outlet. The screen has an upper end and a lower end, and the fluid source is sized and configured to dispense fluid adjacent the upper end for distributing fluid across the screen towards the lower end. The exhaust filter system further includes a fluid reservoir sized and configured to receive fluid from the screen. The fluid reservoir is disposed in fluid communication with the fluid source for recirculating fluid to the fluid filter.
The exhaust filter system may further include a secondary filter sized and configured to remove fluid vapor from the airflow. The secondary filter is disposed in fluid communication with the filter airflow outlet of the fluid filter and the blower. A fluid source sized and configured may be provided to provide fluid to the fluid filter. The fluid source may be sized and configured to receive condensed fluid vapor removed from the airflow by the secondary filter for recirculation to the fluid filter. The coffee bean roaster may further include a chaff collector sized and configured to remove chaff from the airflow. The chaff collector may be disposed in fluid communication with the roasting drum and the filter airflow inlet of the fluid filter.
Accordingly, the present invention represents a significant advance in the art.